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Bill Kielb

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Everything posted by Bill Kielb

  1. I have used mica clay or micaceous clay to coil construct things. It is pit fired and can be relatively water proof as long as it is hand compressed and burnished a bunch. Google ShumaKolowa, as I recall functional Pueblo pottery. Fun to try, fun to learn, and lots of mica everywhere! Seriously it was a good experience and pit firing finish is the norm.
  2. I personally see an interesting similarity yet contrast in the top one and bottom right. They have matching glazes yet different offsetting contrast and the diversity in the texture yet similar textural design would make me want to display them together.
  3. Don’t forget switching at zero crossing, meaning his relays always wait till zero volts and fire. Elements are never subjected to startup at 170 v peak or worst case 340 v. Peak for two phase operation. As well as smoother temperature control allows the overall duty cycle of the element to match the load more practically.
  4. Really nice project and thanks for sharing. If you ever need the PLC code created for the monitor we created ( simple ladder logic for Click PLC stuff) just drop me a message. You are welcome to it.
  5. Nice on both fronts! I was an electrician at age 20 (some time ago) and would offer to help but the distance from Wa to IL is rather significant. I will have to cheer you on from a distance. With respect to the Rpi I was going to drop you a note that said funny, now you have some programming to perfect along with your wares. Sounds like a fun project, hope you can keep us apprised.
  6. Old general filter was to add a small rc filter network to both legs of the thermocouple. They needed to be identical to offset the error and also needed decent capacitors. I was hoping shielded thermocouple would solve your noise issue. Hard to tell from the data you have what magnitude the noise is but likely microvolt average on a .6 to 52 millivolt signal.. Does the thermocouple board auto detect shorted and open circuit thermocouple failures? I only ask because in PLC land temperature transmitters do this for us so we need not have to worry. all still looks great BTW, under three hundred with a decent web server interface! Cool!
  7. Looks pretty nice! I am still curious how hot the SSR gets since we have been debating on retrofitting a kiln or two with ssr replacements downstream of the existing relays. The relays would only serve as an enable during operation or a positive means of disconnect under alarm. My limited research has always indicated the use of a fairly significant heat sink install. Your SSR I believe is rated at about 12000 watts controlling approximately 10000 watts of load so not grossly over sized. At this point it looks like you could fire and be successful with about 6000 watts of power - interesting! snce this is zero crossing it should be kinder to the elements since no 177v peak starts, ever! two thoughts: do you currently have shielded cable for the thermocouple leads? did you install fuse protection for the SSR occasionally in some kilns it is possible to have an element short depending upon how much they have been allowed to crawl out and where they touch.
  8. Relays cheap, almost always need decent heat sink and the probability that they can fail (shorted) in general requires fail safe electromechanical safety so that usually adds to the cost. A slick pseudo method has been to safety enable the existing kiln relays and feed the SSR downstream. We Often see a kiln lid switch inserted in series with this circuit as well. Everything in this loop is generally powered to be safe, interruption anywhere in the safety circuit stops the kiln and terminates the program. Manual operator reset and restart required for many errors accept maybe power outage. I think this relay is pulse width modulated and fires at zero crossing. Right now it appears he is firing 11000 cycles over about 48000 seconds or let’s say one cycle every four seconds average. This is a pretty slow thermodynamic process with a lot of thermodynamic inertia. At just short of 10,000 watts available heating I would be surprised if this does become an issue. Just a gut feeling though, his data will direct him.
  9. Pretty nice data! I will look at noise issue, seem to remember reading type K and Rasberry Pi . Fairly small voltages so twisted pair in a shield (single end ground) might remove enough for a short run. I am not that guy though and have resisted these things in favor of PLC and temp controllers. 46% duty cycle looks nice to me. pid error looks great (is this indicatative of Pv vs Sv?) I would be curious of the temperature rise across the SSR for general heat sink sizing and if pulse width modulated, is this a zero crossing SSR? Seems minimum cycle width would be 1/2 cycle with a max freq. of 120hz. I am not an SSR guy though so most of this stuff maybe sorted out already. Finally - yes, restart for a number of reasons always addressed in almost all processes especially thermodynamic ones. This is really nice, I am pretty lazy and have utilized off the shelf controllers and have recently been looking at WiFi enable stuff for an economically viable kiln control with web interface and logging. Right now still hundreds of dollars and hard to compete with the Bartlett genesis drop in approach using existing relays and multiple zones. Looks great so far, thanks for sharing!
  10. Really nice! It will be interesting to see a fully loaded kiln, the duty cycle of the ssr And how well the pid module performs.
  11. It’s actually simpler than that. We created the monitor using PLC stuff which is an industry staple. Industry has used this equipment for years so there are many really economical ways to do this now. Originally we needed to replace one of the old high limits on the soda Alpine and the quotes we received were in the 1-2k range . Well for less than that we could replace all and digitize the whole room using PLC touch screen stuff so that’s how we ended up creating this. Picture 1 below is a shot of the very economical solo temperature controllers used as high limit and for their communications capability which started the whole thing. These are less than 50 bucks each I believe. Picture 2 is the PLC and touch screen installed in a simple electrical junction box ( no frills enclosure) all for underm1000 bucks as I recall. the interesting part was all of these controls could act stand alone so at any point the user could simply fire using the digital temperatures in the picture and the monitor could be completely shut off. This allowed us to build gradually to our budget and even if something failed it was way better than the hand held pyrometer they were using to fire. of course the monitor has super utility with a web server built in and all sorts of neat stuff too numerous to list. I have a long instructional video below you can skip through, It is for the members. I am working on a shorter version showing how easy this actually was to create and should put it up on the Madison Pottery you tube channel in early January.
  12. Maybe, Removal is probably inevitable. Bores indicate firebrick front and sides, rear wall is uncertain. Top appears to be standard vermiculite and refractory cement. Pretty simple kiln but select brick replacement is possible should they want to pursue that. As far as reusing the burners they are the standard Alpine aweful ones imbeded slightly in the ports with no real flame retention nozzle to speak of so reusing these probably not a wise choice. My guess extend service for a year or so with select brick replacement. At that point they need to debate relocation to a larger building and perhaps their new space would be more conducive and provide more sophisticated choices. Currently if they water inject they would need to add a great deal of designed exhaust and make up air so everything works well together as is in a tight space and they do get spectacular results. next change will likely be a large one.
  13. Pictures as promised. We have two artists that fire soda very differently, Linda Kiepke and Jean Burnett. Linda soda fires cone 6 (Straight Sodium Bicarbonate). Jean fires cone 10 standard soda with reduction. Both lead firing teams and have developed their application methods. As to application everything is injected as dry powder through a blower system. A bit unique! The pictures give a flavor of the work. They produce many unique interesting pieces. The old Alpine was converted, patched and coated with ITC 100. From there the worst areas are simply patched as they become an issue. The ITC 100 actually seems to have limited the interior vapor intrusion into the bricks significantly and we are guessing maybe 100 firings before significant rebuild. I believe they have 20 - 30 firings on it right now. Four injection ports were placed in the sides of the kiln and the front site ports can be used if so desired. The repurposing of the old kiln and purchase of a used Alpine allowed them to complete the installation including the monitor system, new high limits, new pilot safety on the Soda Alpine, Oxygen probes for both. exhaust blower for the kiln room, combustion air, soda delivery blower, laser, electric throughout, medium pressure gas extension and regulator, and general upgrades for the new (used) Alpine which came from a school and only had a couple firings on it. Too many things to list for about 20K but well worth it in my opinion. The graphic monitor has allowed them to accelerate the reduction learning curve and believe it or not makes it pretty easy to down fire and grow crystals. At some point in the future they will need to rebuild the soda kiln or purchase a new one. For now they are firing away and having fun. Pictures: Linda Kiepke Vase (Cone 6 soda only) Jean Burnett Vase (Cone 10 with reduction) Beginning Body Reduction flame (Today) Beginning Body reduction Monitor screen (Today) Soda Injection (Today) I think we are pleased with the success of this project at this point. It has been a productive journey for all involved.
  14. Been firing it for Over a year now. Firing it today actually (soda) just finished a regular reduction firing in the other kiln yesterday.. They ended up buying a second used Alpine for strictly reduction. I should be there later and will get some pictures of their fired stuff
  15. Just to add a couple of pictures of the removable Soda Kiln Probe. There were some complaints about a trip and fall hazard but as you can see the entire arrangement sticks out about the same amount as the port plugs whether in the door or stored during soda application. It is really a clean installation. We chose this method because pendant mounting would make the thing really dangerous when extracted and 2000 degrees during soda injection. Regardless, this is their tight little space to fire and does illustrate the electrical isolation of this probe necessary when it is used with the PLC graphic equipment instead of the DMM provided.
  16. Our fixed probe is similar to yours with respect to the penetration in the kiln (See picture). We have little difficulty sensing the atmosphere and have come to the realization that during their initial reduction period (Body reduction, if you will) they need 4"-5" gas pressure to eliminate dead spots in the old updraft Alpine. As a result, they have no dead spots, period. If the probe is sensing wild swings in reduction it is because the kiln is not filled sufficiently. With respect to the removeable probe the imbed depth was intentional so folks would intentionally leave sufficient space for the probe and to minimize any effect due to door seal leaks, port leaks etc... and to provide the user with confidence that it is sensing the environment. Interestingly both kilns are married to their respective high temperature ceramic protection tubes. Mechanically with a clamp on the fixed kiln and cemented on the removeable probe. In each case the back end of this tube has fiber insulation inserted so there is no chance of the kiln environment leaking out. It appears you have tape which seems to be holding up ok. An interesting quirk with the probes is that the head of the probe must remain ungrounded as a result of how they utilized the feeds internally opting for three wire operation. This required that both probe housings be isolated from ground. Since both kilns are well grounded the isolating configurations you see were chosen. This issue does not surface during the use of the Digital meter as it has no reference to earth ground. Their entire system and kilns are located indoors and designed and installed to last many many years so thermal isolation, rigid permanent mounting and serviceability etc... all designed in with a monitor that has too many features to list and serves both kilns with concurrent firing capability. You 02 probe looks brand new !
  17. Sorry about that but it did bring a wry smile to my face and memories of tools falling off a 20’ ladder near some formerly really nice finished wares.
  18. Nice, looks like it is sturdy. They choose to use their probe to do soda with reduction. They are accustomed to reducing by probe but certainly can do this by eyesight with less accuracy. picture of their fixed probe kiln attached, they use a PLC to monitor both kilns so all the wiring is tied out of the way and thermally isolated. Current transducers on thermocouples are to transmit data over a distance to the monitor. This is a very tight area containing two kilns so available space is at a premium.
  19. Great question. I was fortunate enough to take my work bench on the road to build a bench for a friend which went to sofa and sold successfully for at least four figures. Loved her art and glad it sold! Feel good about the bench as it had to support at least three hundred pounds without deflection to crack any of her tiles. Fun project and success always makes the labor part forgettable. Picture of it going to its new owner attached. December project (s) Complete a couple glaze formulations to work well over heavy underglaze on low expansion porcelain. Test are going well and should be able to publish after the first of the year. Additional December project was to get at least four basic throwing videos done for newbies in the studio. Three done so far so we will just keep plugging along. last project was to begin creating a glaze workshop for the resident artist at the studio. Just beginning this one and have outlined it. Thus far I like the direction and content.
  20. Its not nearly in the way and training is way important including not dropping 2000 degree site port plugs on your toes or the other hazards of operating a gas kiln. Seriously it is well placed and hard to snag now the other hazards, not so forgiving
  21. Yep, definitely important to excercise reasonable safety. 3/4” branded shell protects it pretty well and positionally its very noticeable and reasonably out of th way.. Folks can trip and fall though especially when injecting soda. No one is allowed to operate this without proper training of course since here are many more dangers.
  22. Door on this kiln is 6” so simply insert until stop. No need for bracket. We embedded this deeper in the kiln so they would be required to leave space in the kiln for it and it would seal at the door opening., and be less sensitive to any door leaks in general. Fixed install only penetrates the kiln by 1” and still has protection tube
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